Bug on #XmlElementWrapper inside <xml-elements> MoXy? - eclipselink

Question

I found a tricky bug:
If I define the metadata-xml-binding as below
<?xml version="1.0"?>
<xml-bindings xmlns="http://www.eclipse.org/eclipselink/xsds/persistence/oxm"
package-name="package" xml-mapping-metadata-complete="true">
<xml-schema element-form-default="QUALIFIED" />
<java-types>
<java-type name="SearchResult">
<xml-root-element/>
<java-attributes>
<xml-element java-attribute="count"/>
<xml-element java-attribute="requestParameters"/>
<xml-element java-attribute="pageSize"/>
<xml-element java-attribute="sortDirection"/>
<xml-elements java-attribute="results">
<xml-element name="GaDictionaryElement" type="it.ga.model.GaDictionary">
<xml-element-wrapper name="GaDictionaryElementWrapper" />
</xml-element>
<xml-element name="OrganizationUnitElement" type="it.ga.model.OrganizationUnit">
<xml-element-wrapper name="OrganizationUnitElementWrapper" />
</xml-element>
<xml-element name="PersonElement" type="it.ga.model.Person">
<xml-element-wrapper name="PersonElementWrapper" />
</xml-element>
<xml-element name="Empty" type="java.lang.String">
<xml-element-wrapper name="EmptyWrapper" nillable="true"/>
</xml-element>
</xml-elements>
</java-attributes>
</java-type>
</java-types>
</xml-bindings>
I have seen that the <xml-element-wrapper> tag doesn't work because it's into the <xml-element> tag that is surrounded from the <xml-elements> tag. So I was looking to find a way to solve this problem in a clean way. Because I need an empty node when the List<?> results of my class is empty.
A really bad workaround is creating a lot of different binding file as many type I have for the List<?> results but I don't like that!
Furthermore did someone try to create a binding file that could be useful for classes that implements a particular interface? E.g. In a way that I can see only the property of the object defined on the binding file and specifying as type the name of the interface? I have seen this: [blog]: http://blog.bdoughan.com/2010/07/moxy-jaxb-map-interfaces-to-xml.html#comment-form

Answer 1

You aren't permitted to have an <xml-element-wrapper> per <xml-element> inside an <xml-elements> in terms of what MOXy will process. You could have a single <xml-element-wrapper inside of <xml-elements>.
oxm.xml
<?xml version="1.0"?>
<xml-bindings
xmlns="http://www.eclipse.org/eclipselink/xsds/persistence/oxm"
package-name="forum16943280"
xml-mapping-metadata-complete="true">
<java-types>
<java-type name="SearchResult">
<xml-root-element/>
<java-attributes>
<xml-elements java-attribute="results">
<xml-element name="GaDictionaryElement" type="forum16943280.GaDictionary"/>
<xml-element name="OrganizationUnitElement" type="forum16943280.OrganizationUnit"/>
<xml-element-wrapper name="results"/>
</xml-elements>
</java-attributes>
</java-type>
</java-types>
</xml-bindings>
SearchResult
package forum16943280;
import java.util.List;
public class SearchResult {
private List<Object> results;
public List<Object> getResults() {
return results;
}
public void setResults(List<Object> results) {
this.results = results;
}
}
GaDictionary
package forum16943280;
public class GaDictionary {
}
OrganizationUnit
package forum16943280;
public class OrganizationUnit {
}
Demo
package forum16943280;
import java.io.File;
import java.util.*;
import javax.xml.bind.*;
import org.eclipse.persistence.jaxb.JAXBContextProperties;
public class Demo {
public static void main(String[] args) throws Exception {
Map<String, Object> properties = new HashMap<String , Object>();
properties.put(JAXBContextProperties.OXM_METADATA_SOURCE, "forum16943280/oxm.xml");
JAXBContext jc = JAXBContext.newInstance(new Class[] {SearchResult.class}, properties);
Unmarshaller unmarshaller = jc.createUnmarshaller();
File xml = new File("src/forum16943280/input.xml");
SearchResult result = (SearchResult) unmarshaller.unmarshal(xml);
Marshaller marshaller = jc.createMarshaller();
marshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, true);
marshaller.marshal(result, System.out);
}
}
input.xml/Output
<?xml version="1.0" encoding="UTF-8"?>
<searchResult>
<results>
<OrganizationUnitElement/>
<OrganizationUnitElement/>
</results>
</searchResult>
input.xml/Output
<?xml version="1.0" encoding="UTF-8"?>
<searchResult>
<results>
<GaDictionaryElement/>
<GaDictionaryElement/>
</results>
</searchResult>

Answer 2

If you want separate element wrappers you could split the results property up per type.
SearchResult
package forum16943280;
import java.util.List;
public class SearchResult {
private List<GaDictionary> gaDictionaryResults;
private List<OrganizationUnit> organizationUnitResults;
public List<GaDictionary> getGaDictionaryResults() {
return gaDictionaryResults;
}
public void setGaDictionaryResults(List<GaDictionary> results) {
this.gaDictionaryResults = results;
}
public List<OrganizationUnit> getOrganizationUnitResults() {
return organizationUnitResults;
}
public void setOrganizationUnitResults(
List<OrganizationUnit> organizationUnitResults) {
this.organizationUnitResults = organizationUnitResults;
}
}
oxm.xml
<?xml version="1.0"?>
<xml-bindings
xmlns="http://www.eclipse.org/eclipselink/xsds/persistence/oxm"
package-name="forum16943280"
xml-mapping-metadata-complete="true">
<java-types>
<java-type name="SearchResult">
<xml-root-element/>
<java-attributes>
<xml-element
java-attribute="gaDictionaryResults"
name="GaDictionaryElement">
<xml-element-wrapper name="GaDictionaryElementWrapper"/>
</xml-element>
<xml-element
java-attribute="organizationUnitResults"
name="OrganizationUnitElement">
<xml-element-wrapper name="OrganizationUnitElementWrapper"/>
</xml-element>
</java-attributes>
</java-type>
</java-types>
</xml-bindings>
Demo
package forum16943280;
import java.io.File;
import java.util.*;
import javax.xml.bind.*;
import org.eclipse.persistence.jaxb.JAXBContextProperties;
public class Demo {
public static void main(String[] args) throws Exception {
Map<String, Object> properties = new HashMap<String , Object>();
properties.put(JAXBContextProperties.OXM_METADATA_SOURCE, "forum16943280/oxm.xml");
JAXBContext jc = JAXBContext.newInstance(new Class[] {SearchResult.class}, properties);
Unmarshaller unmarshaller = jc.createUnmarshaller();
File xml = new File("src/forum16943280/input.xml");
SearchResult result = (SearchResult) unmarshaller.unmarshal(xml);
Marshaller marshaller = jc.createMarshaller();
marshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, true);
marshaller.marshal(result, System.out);
}
}
input.xml/Output
<?xml version="1.0" encoding="UTF-8"?>
<searchResult>
<GaDictionaryElementWrapper>
<GaDictionaryElement/>
<GaDictionaryElement/>
</GaDictionaryElementWrapper>
</searchResult>
input.xml/Output
<?xml version="1.0" encoding="UTF-8"?>
<searchResult>
<OrganizationUnitElementWrapper>
<OrganizationUnitElement/>
<OrganizationUnitElement/>
</OrganizationUnitElementWrapper>
</searchResult>

Answer 3

<?xml version="1.0"?>
<xml-bindings xmlns="http://www.eclipse.org/eclipselink/xsds/persistence/oxm"
package-name="it.core.widget.dto" xml-mapping-metadata-complete="true">
<xml-schema element-form-default="QUALIFIED" />
<java-types>
<java-type name="JaxbSearchResult" xml-accessor-type="NONE">
<xml-root-element />
<xml-type prop-order="count pageSize requestParameters sortDirection results" />
<java-attributes>
<xml-element java-attribute="count" />
<xml-element java-attribute="requestParameters" />
<xml-element java-attribute="pageSize" />
<xml-element java-attribute="sortDirection" />
<xml-elements java-attribute="results">
<xml-element name="gaDictionaryElement" type="it.ga.model.GaDictionary" />
<xml-element name="organizationUnitElement" type="it.ga.model.OrganizationUnit" />
<xml-element name="personElement" type="it.ga.model.Person" />
<xml-element-wrapper />
</xml-elements>
</java-attributes>
</java-type>
</java-types>
</xml-bindings>
This is the xml and works if I remove <xml-element-wrapper />
Furthermore without that tag it produces the above output
<?xml version="1.0" encoding="UTF-8"?>
<jaxbSearchResult>
<count>3</count>
<pageSize>30</pageSize>
<style>1</style>
<discriminator>equipment</discriminator>
<posting>1</posting>
<CLEAR>1</CLEAR>
<sortDirection> ASC </sortDirection>
<gaDictionaryElement>
<id>24964</id>
<startDate>2013-03-12T00:00:00</startDate>
<gaDictionaryMap />
<booleanMap />
<integerMap />
<numberMap />
<clobMap />
<parentGaDictionaryLinkSet />
<childGaDictionaryLinkSet />
<displayValue>Equipment 2</displayValue>
</gaDictionaryElement>
<gaDictionaryElement>
<id>24962</id>
<startDate>2013-03-12T00:00:00</startDate>
<gaDictionaryMap />
<booleanMap />
<integerMap />
<numberMap />
<clobMap />
<parentGaDictionaryLinkSet />
<childGaDictionaryLinkSet />
<displayValue>Equipment 1</displayValue>
</gaDictionaryElement>
<gaDictionaryElement>
<id>25185</id>
<startDate>2013-04-22T00:00:00</startDate>
<gaDictionaryMap />
<booleanMap />
<integerMap />
<numberMap />
<clobMap />
<parentGaDictionaryLinkSet />
<childGaDictionaryLinkSet />
<displayValue>Attrezzatura test</displayValue>
</gaDictionaryElement>
</jaxbSearchResult>
I need to wrap gaDictionaryElement accordingly the type that has been marshalled.
Any help is appreciated.
Furthermore did someone try to create a binding file that could be useful for classes that implements a particular interface? E.g. In a way that I can see only the property of the object defined on the binding file and specifying as type the name of the interface? I have seen this: [blog]: http://blog.bdoughan.com/2010/07/moxy-jaxb-map-interfaces-to-xml.html#comment-form